This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A009428 #17 Feb 09 2014 05:40:21
%S A009428 0,1,-1,5,-12,29,-165,993,-7056,62649,-540225,5044445,-56372844,
%T A009428 685980437,-8868937077,124034330553,-1855540686720,29570974192753,
%U A009428 -502444027531233,9041323571823925,-171561171727515820,3427632445624110605
%N A009428 Expansion of e.g.f. log(1+x)/cos(tanh(x)).
%H A009428 Vincenzo Librandi, <a href="/A009428/b009428.txt">Table of n, a(n) for n = 0..200</a>
%t A009428 With[{nn=30},CoefficientList[Series[Log[1+x]/Cos[Tanh[x]],{x,0,nn}], x]Range[0,nn]!] (* _Harvey P. Dale_, Oct 06 2011 *)
%K A009428 sign,easy
%O A009428 0,4
%A A009428 _R. H. Hardin_
%E A009428 Extended with signs by _Olivier Gérard_, Mar 15 1997
%E A009428 Corrected Mathematica program, Harvey P. Dale, Oct 06 2011